https://c1.iggcdn.com/indiegogo-media-prod-cld/image/upload/c_limit,f_auto,w_620/v1442820026/ymlybfwbuh9pikzqjnfk.png
->
https://c1.iggcdn.com/indiegogo-media-prod-cld/image/upload/c_limit,f_auto,w_2000/v1442820026/ymlybfwbuh9pikzqjnfk.png
Now you can read text in the sketch
Probably they can be reuploaded in better quality with same URL trick, or searched somewhere else on the internet in better quality. This specifc iggcdn.com gives files in *.WEBP image format which I converted to PNG